Attachment D - Stormwater and Water Quality report

                                                                                                                  Callaghan & Toth

CONTENTS
1.0 SUMMARY ......................................................................................................................... 5
2.0 INTRODUCTION ............................................................................................................... 5
3.0 DESCRIPTION.................................................................................................................... 7
   3.1 Contaminated Land: ......................................................................................................... 7
   3.2 Proposed Works ............................................................................................................... 8
4.0 WATER QUALITY MANAGEMENT PLAN ................................................................. 10
   4.1 Background Lower Mill Site Stormwater Management ................................................ 10
   4.2 Proposed On-Site Stormwater Treatment Process ......................................................... 10
   4.3 MUSIC Model ................................................................................................................ 11
      4.3.1 Source Nodes .......................................................................................................... 11
      4.3.2 Treatment Nodes ..................................................................................................... 12
      4.3.3 Rainfall Data ........................................................................................................... 13
   4.4 MUSIC Modelling Results ............................................................................................. 15
      4.4.1 Water Quality Objectives ........................................................................................ 15
      4.4.2 Assessment of Results............................................................................................. 16
5.0 FLOODING ASSESSMENT SUMMARY ....................................................................... 17
   5.1 Existing Conditions ........................................................................................................ 17
   5.2 Proposed Drainage System............................................................................................. 17
6.0 PROPOSED REMEDIATION OF STORMWATER DEVICES ..................................... 18
   6.1 Biobasins ........................................................................................................................ 18
7     CONCLUSIONS & RECOMMENDATIONS ..................................................................... 19
APPENDIX A       - MUSIC Results ............................................................................................ A
APPENDIX B       - Site Management Plan – Contaminated Land .............................................. B
APPENDIX C       - IPWEAQ Standard Drawings....................................................................... C




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2001 Lower Mill Carpark Extension SWMP                                                                        February 2020